Radiotherapy and brachytherapy treatments for prostate cancer

Are you looking for radiotherapy sessions for prostate cancer? Brachytherapy can be used alone (monotherapy) or in combination with other treatment regimens, such as external radiotherapy or hormone therapy. Until the mid-1980s, the treatment method used for the treatment of prostate cancer with brachytherapy utilized permanent implants.

In 1992, high dose rate (HDR) brachytherapy system was added. This type of brachytherapy for prostate cancer introduced a series of very beneficial novelties for the fight against cancer.

Below is a description of both modalities of prostate brachytherapy, offering each patient the most appropriate and most efficient treatment possible on a case-by-case basis.

HDR (High Dose Rate) brachytherapy is usually used in combination with external conformal radiotherapy and/or hormone therapy. It may also be used as rescue treatment for cases where the tumor has relapsed after radical prostatectomy, external beam radiotherapy or seed implant. HDR brachytherapy as an overdose after external radiotherapy is recommended in male patients who:

• Is in any stage of the localized disease, Stages T1-T3b.
• Present extra-capsular extension or involvement of the seminal vesicles.
• Have any PSA value without evidence of metastatic disease.
• Have any degree of Gleason score.
• Present perineural invasion evidenced by CT, MRI or biopsy.
• Have had previously undergone a transurethral resection (TUR).
• Present any size of prostate.
• Have or have not previously received radiotherapy treatment to the prostate.
• have been previously treated by external radiotherapy and/or permanent implants and currently have a recurrent disease (local failures).
• Present local recurrences after radical prostatectomy.

In some selected cases, high dose rate brachytherapy treatment can also be used as a single treatment without external radiotherapy nor hormone therapy. These cases could also be candidates for brachytherapy using seeds but this method is not recommended due to the previously performed transurethral resection.

If permanent Iodine 125 seed implants can be successfully used as monotherapy, HDR brachytherapy implants can also be used successfully without the need for further complementary treatments.

A selected group of patients is eligible for the treatment according to the HDR Monotherapy protocol.

As can be seen, patients who have had a previous TUR (transurethral resection) are NOT excluded. High Dose Rate (HDR) brachytherapy procedure consists of 1 implant that delivers the dose in 4 fractions.

The doctor determines the type of treatment the patient should follow by reviewing the patient's history and the latest analyzes. This is done during the first visit. If necessary, a preoperative examination (full blood panel with coagulation tests, chest X-ray and ECG) and extension investigation are then requested, and the patient must deliver the results of these examinations at the next visit during which the patient is given an appointment for the implantation.

Epidural anesthesia is performed on the day of the implantation. The patient is placed in the treatment position that gives the physician wide access to the perineum. For the application, a guide support and flexible treatment catheters are used.

In real time and with ultrasound guidance, the prostate and its limits are located, and the support of the appropriate size is placed on the perineum and directed so that it adequately covers the entire prostate. The support is held manually while the flexible tubes are inserted, so that the doctor has greater control of the placement of the tubes, angulating and directing the progression of these tubes in the prostate. It is possible to adequately treat any size of prostate, perineural or extracapsular extension or involvement of seminal vesicles that may exist using the adequate size of the support and guiding the placement of the guide tubes under the ultrasound. This great capacity of adaptation of the HDR implant allows treating even large prostates without the need to increase the number of needles inserted. The pubic arch occasionally interferes with the placement of rigid needles, but the pubis is no longer a problem with the use of flexible guide tubes.

When the flexible tubes are in the position required, the support is sutured to the perineum to stabilize the implant. A radiopaque catheter is placed in the bladder to facilitate urinary drainage and the visualization of the urethra in the radiographic images. A catheter is also usually inserted into the rectum to administer radiopaque contrast that allows its identification on an x-ray. Once the patient recovers from the spinal anesthesia, s/he is taken to the simulation room for a CT scan.

After obtaining the images, the patient waits in a room of our center until the treatment plan is generated using the dedicated computers, called planners. The parameters of the treatment equipment are calculated, so that the prostate receives the proper dose while minimizing the dose received by the urethra, rectum and bladder.

Once the physicist and the doctor have approved the treatment plan, the patient is transferred to the treatment room, where the catheters are connected to the equipment. Before carrying out the treatment, the system itself verifies that all the tubes are correctly connected and that the treatment can be carried out without problems. From this moment, the patient is alone in the treatment room, but remains constantly monitored through closed-circuit television and intercom.

The patient does not feel any pain or discomfort. Generally, "clicks" are heard as the source progresses through each of the guide tubes. The mean duration of the treatment is 10 to 20 minutes. After the treatment, the source returns to the storage. The patient is not radioactive at any time and is returned to the room and a few hours later, the second treatment is performed.

When necessary, the second implant is implanted one week later following the same procedure described above.

This imaging technique is used to evaluate the implant using CT-based 3D scan images. The image shows the implant in 3D. It can be rotated to see the radiation coverage of the prostate and the proximity to other structures, such as the rectum.

Permanent seed implants are a form of low dose-rate interstitial brachytherapy. The isotope used is Iodine-125. These small seeds (1mm x 5mm) are inserted in the prostate, where they remain for life while radioactively decaying.

Permanent seed implants are used as monotherapy in cases of prostate tumors with a high probability of being limited to the prostate, without any need to combine it with external radiotherapy or hormone therapy. Permanent implants are ideal in these cases as they are inserted in a day-hospital environment, allowing the discharge of the patient within a few hours after the implantation. The eligibility criteria for permanent seed implants are:

• Stage T1-T2b.
• Prostate volume < 60 cc.
• PSA<=10.
• Gleason <= 6.
• Prostate volume < 60 cc.
• No perineural extension.
• No previous transurethral resection (RTU).

In the first visit, the patient's history is reviewed and the IMOR Institute's doctor determines the type of treatment to be followed, informing the patient of the characteristics of the treatment. If necessary, a preoperative workup is requested (full blood panel, with coagulation tests, ionogram, chest X-ray and ECG) which should be brought to the next visit.

At the time of implantation, the patient is placed in the treatment position once under epidural anesthesia. The guide plate for the needles is placed on the perineum, the area between the scrotum and the anus. A transrectal ultrasound scan is performed in the treatment position to determine the shape, position and size of the prostate. The prostate image is electronically scanned and transferred to the planning computer, where it is superimposed on a calibrated grid. The physicist makes exhaustive calculations to determine the position to be occupied by each of the seeds and their coordinates to administer a suitable dose to the entire prostate, protecting the urethra and rectum. This results in a map of the prostate and a list of the coordinates of the brachytherapy needles and the number of seeds each one must carry. The physician introduces the guide needles one by one through the holes in the guide plate, which has been previously selected by the planning computer, passing through the perineum until the prostate under the guidance of sonographic images. When each needle is in position, the seeds are introduced according to the planning indications. The usual number of seeds placed is variable, but it is often around 50 to 100, depending on the size of the gland.

It can be verified that the reference isodose adequately covers the entire prostate by showing the three-dimensional dose distribution. If there is an area that is poorly covered, additional seeds can be placed in the nearby sites until the entire prostate is properly treated.

Brachytherapy is a very effective and well-tolerated treatment.

Current experience shows that its long-term results are at least the same as those obtained with radical surgery, but with the great difference of quality of life that results after tthe reatment. The side effects of brachytherapy are minimal and above all transient, resolving completely after a few weeks of treatment.

The IMOR Institute, Medical Institute of Oncological Radiotherapy, is a pioneer in the technique of prostate brachytherapy. It has the most advanced technical tools of our days to carry out the appropriate technique in each case. In other words, we are always in search of new methods that ensure fewer side effects and better health for the patient and decrease the high risk caused by other alternative therapies.

We have an effective treatment for prostate cancer. Our highly qualified team is at your disposal any time, offering personalized attention and the highest quality care.